Was the first person to propose the idea of moving continents as a scientific hypothesis.
a. alfred wegener
b. abraham ortelius
c. antonio snider-pelligrini
d. charles richter

What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 480 ? the index of refraction of the film is 1.34, and there is air on both sides of the film. express your answer in nanometers. hint 1. how to approach th